Establishment of Cell Line with the FEN-1 Gene Blocked by Its Antisense.

FEN-1 is a structure-specific endo/exonuclease, which is involved in the process of both DNA duplication and DNA repair. In this work a mammalian expression vector expressing antisense FEN-1 gene fragment pMAMneoAmp(-)FNB(-) was constructed, after cloning the NcoI-BamHI fragment of FEN-1 gene into the mammalian expression vector pMAMneoAmp(-) in antisense orientation. After FL cell was transfected with pMAMneoAmp(-)FNB(-) and selected by G418, the FL-FEN-1(-) cell line, in which the FEN-1 gene expression was blocked, was established. It was found that the growth of FL-FEN-1(-) was decreased upon the induction with dexamethasone and its T(D) was 3.03 d, while the T(D) of controls FL and FL-M induced with dexamethasone was 2.03 and 2.22 d, respectively, and the T(D) of the FL-FEN-1(-) cell without dexamethasone was 2.38 d.